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Efficient Dairy production

Dairy farms today face challenges and opportunities fuelled by rapidly rising energy costs and concerns about environmental impacts. Dairy farms use more energy than almost any other agricultural operation.

Why be energy efficient?

Determining the best energy efficiency and energy management opportunities for dairy farms will help reduce energy costs, enhance environmental quality and increase productivity and profitability.

This is especially true for the south west, which is home to half a million dairy cows, and there is massive scope for the region's dairy farmers to become more competitive and lower the overhead costs of the milking operation. For help and advice register for a free Resource Efficiency for Farmers visit, which will help you analyse the energy usage on your farm and look at ways to become more efficient.

How can I save energy on my farm?

Record the amount of electricity being used on the farm at regular intervals.

Compare energy use of similar operations to your output and to previous consumption and investigate any large variations.

Compare your tariff to other options and remember to look at the notice period required to terminate your current contract.

Use cheaper night time electricity, especially for water heating.

Insulate water heaters and pipework to minimise losing heat that you are paying for.

Dairy energy consumption

This chart shows what energy is used for on an average dairy farm. This is taken from data that includes results from America and the UK (Peterson 2008)

If you are interested in becoming more energy efficiency on your farm then click here to go to the Resource Efficiency for Farmers (R4F) page to register for a free one-to-one visit. Alternatively click here to read a case study of a farmer who has implemented energy saving equipment in his dairy

Variable speed motors

These can have a range of applications, most commonly as vacuum pumps, but can also be applied to milk pumps irrigation, and ventilation systems.

Variable speed vacuum pumps

Current vacuum pumps operate at a constant speed to provide the vacuum requirements for milking. Variable speed vacuum pumps are designed to meet capacity required when it is needed.

The addition of a variable speed drive pump eliminates the need for a conventional regulator because less energy is delivered to the motor, and operating speeds are reduced.

By maintaining a constant vacuum level and only producing necessary amounts of air flow, energy cost savings of up to 60% can be made. The noise level is also greatly reduced allowing for a gentler parlour environment.

There are also reduced maintenance costs and less wear - leading to an extended life compared with a conventional oil vane pump.

Milk cooling

Cooling milk accounts for the highest energy cost associated with the milking process. Milk needs to be cooled from its harvested temperature of 35-37°C to 3°C to maintain high milk quality and low bacterial counts. There are various options to help cool the milk, including heat exchangers and variable speed milk pumps.

Heat exchangers

These are used for pre-cooling raw milk - transferring the heat from the milk to an intermediary cooling fluid (usually water). Installing a heat exchanger to pre-cool milk prior to entry to the bulk tank can reduce energy consumption by 60%.

Variable speed milk pumps

The use of a variable speed milk pump allows the milk to be pumped through the plate cooler at a more consistent speed, allowing the plate coolers to operate more efficiently and resulting in greater milk cooling. It also allows more heat to be extracted by the plate cooler, and reduces the energy demand on the bulk tank. Milk can be cooled by an extra 15 - 20 degrees by installing a variable speed milk pump.

Heat recovery units

During the process of cooling milk, heat is rejected from the condenser coil of the refrigeration system. It is possible to recover this by passing the hot refrigeration gas through a heat exchanger which is immersed in water. Water temperatures of over 50 °C can be achieved by using this technique.

The water heating system needs to be carefully configured so that the heat recovery can deliver the maximum benefit without compromising the operation of the milk cooling system. Depending on the number of cows being milked, the water storage tank should be sized to provide enough hot water for one milking.

Energy Management

Did you know?

A 20% cut in energy costs can represent the same bottom line benefit as a 5% increase in sales

On most farms, savings of 10-20% of energy costs can often be made with minimal capital outlay

Heating, field operations, ventilation, lighting, air circulation and refrigeration equipment are the biggest energy users in agriculture, where efficiency improvements can provide the most significant savings

Useful tools

Interested in how much energy you are using? Head to the Carbon Trust website and download the interactive tool that will help you identify the key actions that you can undertake at your site to save energy and reduce carbon emissions.

Interested in fuel saving strategies? Click here to go to the Efficient 20 fuel consumption database a tool for monitoring your fuel usage and see the effects of applying some of the fuel-saving techniques.

The importance of monitoring energy usage

In order to look at reducing energy use on-farm, it is important to first know how much you are using. Energy efficiency can be an important step in reducing costs on-farm, and can be achieved relatively simply in many situations. A recent report looking at resource management practices on farms in the south west found that 68% of farms surveyed were monitoring energy efficiency, and 31% were not monitoring energy usage. The graph below shows the breakdown per farm type.